U.S. patent application number 12/221166 was filed with the patent office on 2009-05-28 for bag and article of manufacture.
Invention is credited to David P. Cameron, Roger B. Fielder, George Scott Kerr, Lawrence Andrew Schumacher, Barry Stanley Shantz.
Application Number | 20090136163 12/221166 |
Document ID | / |
Family ID | 39811994 |
Filed Date | 2009-05-28 |
United States Patent
Application |
20090136163 |
Kind Code |
A1 |
Kerr; George Scott ; et
al. |
May 28, 2009 |
Bag and article of manufacture
Abstract
Disclosed is an article of manufacture including bag having a
front surface; a rear surface; two side surfaces each having a
gusset therein and connecting the front and rear surfaces; a
flattenable bottom surface formed by connecting the front, rear,
and side surfaces; and a top surface formable by connecting the
front, rear, and side surfaces. The bag has a height, a width, and
a depth, and defines an internal volume. The bag is sealable and
has a seal strength of at least about 1,600 pounds per square inch.
The bag is formed from a plastic laminate having a thickness of
from about 130 to about 200 microns and a tensile strength of at
least about 3,400 pounds per square inch. The article of
manufacture also includes at least about 15 pounds of a
particulate, flowable composition contained therein. The bag can
also have a closure system comprising a non-reusable closure and a
reusable closure. Also included are methods, using the article of
manufacture, of enhancing palatability of an oxidizable,
particulate, flowable composition contained therein.
Inventors: |
Kerr; George Scott; (Mason,
OH) ; Schumacher; Lawrence Andrew; (Trenton, OH)
; Shantz; Barry Stanley; (Cincinnati, OH) ;
Cameron; David P.; (Canandiagua, NY) ; Fielder; Roger
B.; (Shreveport, LA) |
Correspondence
Address: |
THE PROCTER & GAMBLE COMPANY;Global Legal Department - IP
Sycamore Building - 4th Floor, 299 East Sixth Street
CINCINNATI
OH
45202
US
|
Family ID: |
39811994 |
Appl. No.: |
12/221166 |
Filed: |
July 31, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60962979 |
Aug 2, 2007 |
|
|
|
Current U.S.
Class: |
383/120 ;
383/103 |
Current CPC
Class: |
Y02W 30/807 20150501;
B65D 2207/00 20130101; Y02W 30/80 20150501; B65D 33/25 20130101;
B65D 31/10 20130101 |
Class at
Publication: |
383/120 ;
383/103 |
International
Class: |
B65D 30/20 20060101
B65D030/20; B65D 33/01 20060101 B65D033/01 |
Claims
1. An article of manufacture comprising: a.) a bag comprising: i.)
a front surface; ii.) a rear surface; iii.) two side surfaces each
having a gusset therein and connecting said front and said rear
surfaces; iv.) a flattenable bottom surface formed by connecting
said front, said rear, and said side surfaces; and v.) a top
surface formable by connecting said front, said rear, and said side
surfaces; said bag having a height, a width, and a depth, and an
internal volume; wherein said bag is sealable and has a seal
strength of at least about 1,600 pounds per square inch; and
wherein said bag comprises a plastic laminate having a thickness of
from about 130 to about 200 microns and a tensile strength of at
least about 3,400 pounds per square inch; and b.) at least about 15
pounds of a particulate, flowable composition contained
therein.
2. The article of manufacture of claim 1 wherein said bag contains
at least about 20 pounds of said particulate, flowable
composition.
3. The article of manufacture of claim 1 The bag of claim 1 wherein
said bag has a ratio of said width to said height of from about 0.4
to about 0.8.
4. The article of manufacture of claim 3 wherein said ratio of said
width to said height is about 0.6.
5. The article of manufacture of claim 1 wherein said bag has a
ratio of said depth to said height of from about 0.2 to about
0.4
6. The article of manufacture of claim 5 wherein said bag has a
ratio of said depth to said height of from about 0.2 to about
0.3.
7. The article of manufacture of claim 1 wherein said bag has a
ratio of said width to a height of from about 0.4 to about 0.8, and
a ratio of said depth to said height of from about 0.2 to about
0.4.
8. The article of manufacture of claim 1 wherein said internal
volume of said bag is at least about 20% greater than a volume
occupied by said composition contained within said bag.
9. The article of manufacture of claim 8 wherein said internal
volume, said depth of said bag, and said gussets, in combination
form a grippable portion near said top of said bag, by which said
bag can be grasped for lifting.
10. The article of manufacture of claim 1 further comprising a
non-reusable closure; wherein said non-reusable closure has a
length that extends along said width of said bag.
11. The article of manufacture of claim 10 wherein said
non-reusable closure comprises a membrane connectable between said
front surface and said rear surface of said bag, said membrane
having a user-facing surface, an outer surface, and a tear strength
of at least about 15 pounds per inch (lbf/in.).
12. The article of manufacture of claim 11 wherein a portion of
said outer surface of said membrane is sealable to said front
surface of said bag, and portion of said outer surface of said
membrane is sealable to said rear surface of said bag.
13. The article of manufacture of claim 11 wherein said membrane
comprises a targeted opening region.
14. The article of manufacture of claim 13 wherein said targeted
opening region has a tear strength of from about 1 to about 15
pounds per inch (lbf/in.).
15. The article of manufacture of claim 13 wherein said targeted
opening region comprises from about 1% to about 90% of the length
of said membrane.
16. The article of manufacture of claim 13 wherein said targeted
opening region comprises from about 1% to about 50% of the length
of said membrane.
17. The article of manufacture of claim 13 wherein said targeted
opening region comprises from about 1% to about 10% of the length
of said membrane.
18. The article of manufacture of claim 13 wherein said targeted
opening region comprises a plurality of perforations in said
membrane.
19. The article of manufacture of claim 13 wherein said targeted
opening region is centered at a midpoint along a width of said
bag.
20. The article of manufacture of claim 11 wherein said membrane
comprises instructional indicia on said user-facing surface
thereof.
21. The article of manufacture of claim 11 wherein said membrane
comprises a material selected from the group consisting of:
ethylene-derived polymer, polypropylene, polyesters, polyolefins,
and combinations thereof.
22. The article of manufacture of claim 21 wherein said membrane
comprises an ethylene-derived polymer selected from the group
consisting of: low density polyethylene, high density polyethylene,
ultra-low density polyethylene, and combinations thereof.
23. The article of manufacture of claim 11 wherein said membrane
has a width of from about 1.5 inches to about 3 inches.
24. The article of manufacture of claim 11 wherein said membrane
has a width of about 3 inches.
25. The article of manufacture of claim 10 wherein said
non-reusable closure is disposed at a top edge of said bag.
26. The article of manufacture of claim 10 wherein said
non-reusable closure is disposed inboard a distance from a top edge
of said bag.
27. The article of manufacture of claim 1 wherein said plastic
laminate is selected from the group consisting of: ethylene-derived
polymer, polypropylene, polyesters, polyolefins, woven
polypropylene, and combinations thereof.
28. The article of manufacture of claim 28 wherein said plastic
laminate has an oxygen transmission rate of less than about 6.5
cc/100 in.sup.2/24 hours.
29. The article of manufacture of claim 28 wherein said plastic
laminate has a moisture vapor transmission rate of less than about
0.1 grams/100 in.sup.2/24 hours.
30. The article of manufacture of claim 1 further comprising a
reusable closure.
31. The article of manufacture of claim 30 wherein said reusable
closure is selected from the group consisting of: a track and a
slider system, a plastic zipper, a metal zipper, a hook and loop
fastening system, a threaded closure device, a pressable sealing
device, a snap sealing device, resealable adhesive, a magnetic
device, an electrostatic device, and combinations thereof.
32. The article of manufacture of claim 30 wherein said reusable
closure is disposable at a top edge of said bag.
33. The article of manufacture of claim 30 wherein said reusable
closure is disposable a distance inboard from a top edge of said
bag.
34. The article of manufacture of claim 1 wherein said bag has a
tip angle of from about 10.degree. to about 50.degree..
35. The article of manufacture of claim 1 wherein said bag has a
tip angle of from about 20.degree. to about 30.degree..
36. The article of manufacture of claim 1 wherein said composition
comprises a dry pet food.
37. An article of manufacture for containing a flowable particulate
composition comprising: a. a burst-resistant bag comprising: i.) a
front surface; ii.) a rear surface; iii.) a flattenable bottom
surface; iv.) two side surfaces each having a gusset therein; and
v.) a top surface; vi.) a closure system comprising a non-reusable
closure and a reusable closure; said bag having a height, a width,
and a depth, and an internal volume; wherein said bag is sealable
and has a seal strength of at least about 1,600 pounds per square
inch; and wherein said bag comprises a plastic laminate having a
thickness of from about 130 to about 200 microns and a tensile
strength of at least about 3,400 pounds per square inch; and b.) at
least about 15 pounds of a flowable particulate composition
contained therein.
38. The article of manufacture of claim 37 wherein said
non-reusable closure comprises a membrane connectable between said
front surface and said rear surface of said bag, said membrane
having a user-facing surface, an outer surface, and a tear strength
of at least about 15 pounds per inch (lbf/in.).
39. The article of manufacture of claim 38 wherein said membrane
comprises a targeted opening region having a tear strength of from
about 1 to about 15 pounds per inch (lbf/in.).
40. The article of manufacture of claim 37 wherein said plastic
laminate has an oxygen transmission rate of less than about 6.5
cc/100 in.sup.2/24 hours.
41. The article of manufacture of claim 37 wherein said plastic
laminate bag has a vapor transmission rate of less than about 0.1
grams/100 in.sup.2/24 hours.
42. The article of manufacture of claim 37 wherein said composition
comprises a dry pet food.
43. A side-gusseted bag comprising i.) a front surface; ii.) a rear
surface; iii.) two side surfaces each having a gusset therein; iv.)
a top surface; and v.) a flattenable bottom surface; wherein said
bag is sealable and has a seal strength of at least about 1,600
pounds per square inch; vi.) a non-reusable closure comprising a
membrane having a targeted opening region, said targeted opening
region having a tear strength of from about 1 to about 15 pounds
per inch (lbf/in.).
44. A method of enhancing palatability of an oxidizable composition
after storage comprising the steps of: a. providing a plastic
laminate bag comprising: i.) two side surfaces each having a gusset
therein; ii.) a closure system comprising a reusable closure and a
non-reusable closure, wherein said non-reusable closure comprises a
membrane having a targeted opening region, said targeted opening
region having a tear strength of from about 1 to about 15 pounds
per inch (lbf/in.); wherein said plastic laminate has a
predetermined oxygen transmission rate and a predetermined water
vapor transmission rate; b. filling said plastic laminate bag with
at least about 15 pounds of a flowable particulate oxidizable
composition; c. sealing said plastic laminate bag closed; thereby
preventing oxidation and spoilage of said composition and enhancing
palatability of said composition contained therein.
45. The method of claim 44 wherein said plastic laminate has an
oxygen transmission rate of less than about 6.5 cc/100 in.sup.2/24
hours.
46. The method of claim 44 wherein said plastic laminate has a
moisture vapor transmission rate of less than about 0.1 cc/100
in.sup.2/24 hours.
47. The method of claim 44 wherein said plastic laminate is
selected from the group consisting of: ethylene-derived polymers,
polypropylene, polyesters, polyolefins, woven polypropylene, and
combinations thereof.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to and the benefit of U.S.
Provisional application 60/962,979, filed on Aug. 2, 2007, which is
hereby incorporated by reference herein in its entirety.
FIELD OF THE INVENTION
[0002] The invention relates generally to bags for containing
particulate, flowable compositions, particularly large, heavy bags
containing particulate, flowable compositions. More particularly,
the invention relates to bags and closure systems for such bags
wherein the bags and closure systems can withstand a drop or fall
from at least about 4 feet without bursting or breaking open. Most
particularly, the invention relates to bags for containing from
about 15 to about 75 pounds of particulate, flowable
composition.
BACKGROUND OF THE INVENTION
[0003] Industries that use and sell large quantities of bulk,
particulate, flowable compositions such as animal food, bulk foods,
coffee, fertilizer, detergent and the like are often faced with the
task of packaging and shipping such compositions in containers
suitable for shipping, handling, retail sale, and consumer
transport and use. For compositions such as bulk animal foods, such
containers are typically paper or plastic bags containing up to
about 75 pounds of food composition. Such containers therefore,
must be able to withstand shipping and handling without breaking
open.
[0004] Bags for containing and handling bulk compositions are made
from various materials and secured closed in various ways depending
on the properties of the bag materials, the properties of the
closure systems, and cost considerations. Materials used for such
bags include burlap, paper, multi-layer, and plastics including
nylon, and woven polypropylene. Closure for one-time use can be
accomplished by stitching, taping, gluing, heat sealing, and/or
ultra sonic welding the containers closed after the containers are
filled with the composition. The cost to produce such bags and
closures varies with the type of bag material and type of closure
used. In the retail pet food industry such bags have typically been
made from multiple layers of paper, plastic, and/or foil, and
stitched, taped, heat sealed and/or ultrasonically welded
closed.
[0005] The materials and closures of such bags are typically
selected to provide the most cost-effective container, considering
material cost, material properties, closure cost, closure
properties, damage and lost product due to bag breakage, etc. Bags
for containing quantities of 15 or more pounds of dry pet food
composition are typically multiple layered paper bags, often lined
with plastic or foil on an interior surface thereof, that are
stitched, taped and/or glued closed.
[0006] However, paper bags do not keep the food compositions
contained therein particularly fresh over time. Oxygen, moisture,
and even perhaps organisms can enter the bags. Thus, in time, the
food may oxidize, become stale, become infested, and generally
become less palatable to the animal and less desirable by the
animal owner. Additionally, bags that are stitched, taped and/or
glued closed can not be resealed once opened. Therefore, many
animal owners resort to emptying the contents of the paper bag into
a storage container that can be easily accessed, easily reclosed,
and that keeps the food fresh.
[0007] Furthermore, such feed bags are typically rectangularly
shaped with very small depth versus height of such bags. Thus, the
bags must be stacked and displayed laying flat on one of the
largest surfaces, usually the front or back surface. Such
orientation, particularly for bags containing 15 or more pounds of
composition, makes the bags difficult to display, and to remove and
lift. If such bags are successfully removed from a store shelf,
they are often deposited on a narrow bottom surface of the bag, and
often fall over. The instability of the bags can be bothersome if
one must keep righting the bag. In addition, if the bag has been
taken home and opened, extensive spillage can result when the bag
tips over.
[0008] Recently, manufacturers have attempted to provide bags that
are reclosable and that provide enhanced spoilage protection for
the contents over time, such that a user does not have to empty a
large, heavy bag into a separate container. Therefore,
manufacturers have begun to supply plastic bags, or paper bags with
plastic or foil linings, and having reclosable features. Plastic,
and plastic or foil lined materials are better moisture and
air/oxygen barriers than for example, paper or burlap, and provide
better protection from spoilage and infestation.
[0009] However, it has been found that many such plastic bags burst
open, when filled with about 15 or more pounds of bulk composition,
and dropped off of a truck, a store shelf, out of a user's vehicle
or grip, or when tipped over. The bursting problem is often
exacerbated when such bags are formed with a reclosable feature.
Such bags can burst at the site of the reclosable feature or at one
or more seals or seams of the bag, or the material forming the bag
itself can tear and cause the bag to burst open. In addition,
plastic bags can be slippery to the touch, and can result in a
greater amount of bags dropped versus other materials such as
paper, nylon or burlap.
[0010] Some manufactures have attempted to solve the problem of
bags bursting at a reclosable feature by placing and sealing a
material over or across the reclosable feature, which the consumer
then removes once the bag is safely at its final destination. Such
an approach is feasible with various paper bags, and quantities of
composition over about 15 pounds in weight. However, many plastic
bags still burst when they contain over about 15 pounds of material
and fall from a height of about 3 feet, whether or not the bags
contain a reslosable feature. Thus, the majority of bags used for
containing greater than about 15 pounds of dry pet food are various
types of paper bags. Other approaches include sealing the inside of
the bag in addition to having a recloseable feature. Using a double
thickness in the reclosable feature is another option. However,
cost can increase prohibitively as more components are added to the
bag.
[0011] Therefore, there is a need for a plastic bag that can
contain amounts of heavy compositions and can withstand a drop from
various heights without bursting open. There is also a need for
such a bag to be reclosable. There is a need for such a bag to also
provide moisture and oxidation barrier protection for the contents.
There is also a need for the bag to be stable when situated upright
on a bottom surface of the bag, and for the bag to be easily
grippable.
SUMMARY OF THE INVENTION
[0012] The present invention relates to articles of manufacture
comprising bags for containing large quantities of particulate,
flowable compositions such as dry pet foods; and methods of
preserving and enhancing palatability of oxidizable, particulate,
flowable compositions such as dry pet foods. The bags of the
present invention are burst-resistant when containing at least
about 15 pounds of a particulate, flowable composition and dropped
from a height of at least about 4 feet, and are proportioned so as
to be stable and resistant to tipping when placed on a bottom
surface thereof. The bags can be reclosable. Such articles, bags,
and methods reduce bag damage and product loss during shipping and
handling, enable the bags to be displayed and sold in a more-easily
visible and liftable orientation, and enable a user to avoid having
to transfer the contents of the bag to a second container for use
of the composition.
[0013] An embodiment of the present invention is an article of
manufacture comprising: [0014] a.) a bag comprising: [0015] i.) a
front surface; [0016] ii.) a rear surface; [0017] iii.) two side
surfaces each having a gusset therein and connecting the front and
rear surfaces; [0018] iv.) a flattenable bottom surface formed by
connecting the front, rear, and side surfaces; and [0019] v.) a top
surface formable by connecting the front, rear, and side surfaces;
[0020] the bag having a height, a width, and a depth, and defining
an internal volume; wherein the bag is sealable and has a seal
strength of at least about 1,600 pounds per square inch; and
wherein the bag comprises a plastic laminate having a thickness of
from about 130 to about 200 microns and a tensile strength of at
least about 3,400 pounds per square inch; and [0021] b.) at least
about 15 pounds of a particulate, flowable composition contained
therein.
[0022] The bag can also have a closure system comprising a
non-reusable closure and a reusable closure.
[0023] An alternative embodiment of the present invention includes
a side-gusseted bag comprising: [0024] i.) a front surface; [0025]
ii.) a rear surface; [0026] iii.) two side surfaces each having a
gusset therein and connecting the front and rear surfaces; [0027]
iv.) a flattenable bottom surface formed by connecting the front,
rear and side surfaces; and [0028] v.); a top surface formable by
connecting the front, rear, and side surfaces; wherein the bag is
sealable and has a seal strength of at least about 1,600 pounds per
square inch; [0029] vi.) a non-reusable closure comprising a
membrane having a targeted opening region, the targeted opening
region having a tear strength of from about 1 to about 15 pounds
per square inch.
[0030] Another embodiment of the present invention is a method of
enhancing palatability of an oxidizable composition after storage,
comprising the steps of: [0031] a. providing a plastic laminate bag
comprising: [0032] i.) two side surfaces each having a gusset
therein and connecting the front and rear surfaces; [0033] ii.) a
closure system comprising a reusable closure and a non-reusable
closure; wherein the non-reusable closure comprises a membrane
having a targeted opening region, the targeted opening region
having a tear strength of from about 1 to about 15 pounds per
square inch; wherein the plastic laminate has a predetermined
oxygen transmission rate and a predetermined water vapor
transmission rate; [0034] b. filling the plastic laminate bag with
at least about 15 pounds of a particulate, flowable oxidizable
composition; [0035] c. sealing the plastic laminate bag closed;
thereby preventing oxidation and spoilage of composition and
enhancing palatability of the composition contained therein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0036] FIG. 1 is a perspective view of a bag of the present
invention.
[0037] FIG. 2 is a perspective view of an alternative embodiment of
the present invention.
[0038] FIG. 3 is a perspective cutaway view showing a bag of the
present invention filled with particulate, flowable
composition.
[0039] FIG. 4 is a top perspective view of a bag illustrating a
non-reusable closure of the present invention.
[0040] FIG. 5 is a cross-sectional side view of the membrane of the
invention.
[0041] FIG. 6 is a perspective view of a bag having a non-reusable
closure partially installed therein.
[0042] FIGS. 7a-c are perspective views of the non-reusable closure
of the present invention illustrating the targeted openable
region.
DETAILED DESCRIPTION OF THE INVENTION
[0043] All measurements made herein art made at 25.degree. C.
unless otherwise designated. The term "particulate, flowable
compositions", as used herein and usable with the present
invention, means compositions including animal feeds including
rodent, dog, cat, horse, goat, cattle, pig, bird, and the like;
detergents; fertilizers; cat litter; bulk foods including grains,
nuts, beans, fruits and the like.
[0044] The term "slack fill", as used herein, means to fill a
container with a composition during manufacturing and/or packaging
such that the composition occupies a volume less than the interior
volume of the container, thereby leaving a "head space", meaning
empty portion of volume, in the container.
[0045] The term "seal", as used herein, means the seal(s) that form
the bag itself, and which are formed by sealing the inner surfaces
of the plastic laminate together; and in addition mean the seals
formed when sealing a non-reusable closure to the top of the bag,
if such a non-reusable closure is used.
[0046] The term "seal strength", as used herein, refers to a
measure of tensile strength at each seal made and used in forming
the bag.
Article of Manufacture
Bag
[0047] The present invention encompasses articles of manufacture
illustrated in FIGS. 1-7. As shown in FIGS. 1 and 2, the article of
manufacture comprises a bag 10 comprising a front surface 12 and a
rear surface 14 extending upwardly from a flattenable bottom
surface 16. Two side surfaces 18 each have an expandable gusset 20
therein connecting front surface 12 and rear surface 14 at opposite
sides of bag 10. The bag 10 also has a flattenable bottom surface
16 that can be formed by connecting front surface 12, rear surface
14 and side surfaces 18. Bag 10 also has a top surface 22 formable
by connecting front surface 12, rear surface 14, side surfaces 18,
and located opposite flattenable bottom surface 16. The bag has a
height H, a width W, a depth D. The height H, width W, and depth D
of bag 10 are defined and measured as internal dimensions of bag
10, measured from the inside surfaces of the bag. The height H is
measured along the front or rear face of the bag from the inside
edge of the bottom seal to the top edge of the bag, not including
any closure. The width is measured across the front or rear face of
the bag from inside of edge seal to inside of edge seal at a
midpoint of the height of the bag. The depth is measured across
either side gusset from edge seal to edge seal at a midpoint of the
height of the bag. The height H, width W, and depth D define an
internal volume V.
[0048] The bag 10 is sealable, by methods commonly known in the
art, such as for example, heat sealing, along at least one edge of
a side surface 18a, 18b, bottom surface 16 and top surface 22. The
bag can also be sealed at each edge 18a, 18b. Such a bag, sealed at
each of the four side edges is referred to as a "quad seal" bag. A
quad seal bag is a preferred embodiment described herein. The seals
of the bag have a seal strength of at least about 1,600 pounds per
square inch. The bag comprises a plastic laminate having a
thickness of from about 130 to about 200 microns. The plastic
laminate has a tensile strength of at least about 3,400 pounds per
square inch.
[0049] The article of manufacture comprises, in addition to the
bag, at least about 15 pounds of a particulate, flowable
composition contained therein. Alternatively, the article of
manufacture comprises at least about 20 pounds of the particulate,
flowable composition, alternatively at least about 30 pounds of the
particulate, flowable composition, and alternatively at least about
40 pounds of the particulate, flowable composition. The article of
manufacture can comprise up to about 75 pounds of particulate,
flowable composition.
[0050] The bag 10 of the article of manufacture of the present
invention is formed to have particular dimensions and a particular
shape. An embodiment of bag 10 of the present invention, as shown
in FIGS. 1 and 2, has a ratio of width W to height H of from about
0.4 to about 0.8. Alternatively, the ratio of width W to height H
is about 0.6. Such a ratio of width W to height H helps to ensure
that bag 10 is stable and resistant to tipping such that bag 10 can
be easily placed and stored on its bottom surface 16. Furthermore,
such a width W to height H ratio distributes forces generated on
the plastic laminate and seals if the bag is dropped, such that the
width W to height H ratio aids in making the bag resistant to
breaking or bursting if dropped.
[0051] Bag 10 also has a ratio of depth D to height H of from about
0.2 to about 0.4. Alternatively bag 10 has a depth D to height H
ratio of from about 0.2 to about 0.3. The depth D is provided by
side gussets 20. The depth D to height H ratio also aids in
ensuring that bag 10 can be easily placed and stored on its bottom
surface 16, and be resistant to tipping. In addition, the depth D
to height H ratio also helps distribute forces generated on the
plastic laminate and seals if bag 10 is dropped, such that the
depth D to height H ratio aids in making bag 10 resistant to
breaking or bursting if dropped.
[0052] Such ratios are not commonly found in commercially available
bags. Most commercially available side gusseted bags have rather
small side gussets, and thus, very small depth to height ratios.
Such small depth to height ratios result in bags that have small
bottom surfaces, and which effectively can not be stood on the
bottom surface without tipping over. Therefore, conventional pet
feed bags must be displayed laid down on either the front or rear
surface, and can not effectively be used throughout the period of
use of the composition contained therein because they do not stand
up well. In addition plastic laminate bags with small side gussets
are much less burst-resistant due to the small surface area of the
sides having the gussets. When such bags are dropped, particularly
on the small, gusseted sides, they are likely to burst due to the
forces created due to the small surface area of the gusseted
sides.
[0053] Therefore, an example combination of ratio of width W to
height H, and ratio of depth D to height H, of a bag of the present
invention, is about 0.6 and about 0.25. A bag 10 of the present
invention, when formed as described, can withstand a drop from at
least about 4 feet, on one of gusseted sides 18, when filled with
at least about 15 pounds of particulate, flowable composition, and
is very stable and resistant to tipping. Thus, such a bag can be
displayed and sold in an upright, vertical position, and can be
easily used as the storage container for the composition contained
therein, throughout the use of the composition.
[0054] As shown in FIG. 3, bag 10 of the present invention also
defines an internal volume V which is at least about 20% greater
than a volume Vc occupied by the composition contained within bag
10, thus creating a head space volume Vh. The bags are slack filled
such that the composition does not occupy the entire internal
volume V of the bag. The 20% head space volume Vh allows bag 10 to
be easily and securely sealed after filling, helps to distribute
forces generated if bag 10 is dropped to help ensure bag 10 is
burst resistant, and, in combination with the depth D and gussets
20, provides a grippable portion 24, as seen in FIGS. 1 and 2 near
the top surface 22 by which bag 10 can be grasped for lifting.
[0055] An embodiment of bag 10 can comprise a non-reusable closure
26, shown in FIG. 4, that can aid in ensuring bag 10 is burst
resistant and can provide a tamper evident indicator. Non-reusable
closure 26 has a length that extends along said width W of bag 10.
Non-reusable closure 26 comprises a membrane 28 connectable between
front surface 12 and rear surface 14 of bag 10. The membrane 28 has
a thickness of from about 170 to about 200 microns. Non-reusable
closure 26 is installed in bag 10 in the machine direction of the
material of membrane 28.
[0056] Membrane 28 has a user-facing surface 30, an outer surface
32 (as shown in FIG. 7), and a tear strength of at least about 15
pounds per square inch, as measured in the transverse or cross
machine direction, by ASTM Method D-882 Standard Test Method for
Tensile Properties of Thin Plastic Sheeting. Non-reusable closure
26 can be disposed at a top edge 34 of bag 10, or alternatively,
can be disposed inboard a distance from top edge 34 of bag 10. In
FIG. 4, non-reusable closure 26 is shown located at top edge 34 of
bag 10.
[0057] As shown in FIG. 5, membrane 28 has a plurality of ribs 36a
on outer surface 32 of membrane 28 which enable outer surface 32 to
be sealable to front surface 12 of bag10, and a plurality of ribs
36b on outer surface 32 of membrane 28 which enable outer surface
32 to be sealable to rear surface 14 of bag 10 to seal bag 10
closed.
[0058] FIG. 6 illustrates a membrane 28 partially installed on a
bag 10. A plurality of ribs 36a (as shown in FIG. 5) on outer
surface 32 of membrane 28 is sealable to an inner surface 12a of
front surface 12 and to a top portion 20a of an inner surface 20b
of gussets 20. A plurality of ribs 36b on outer surface 32 of
membrane 28 is sealable to an inner surface 14a of rear surface 14
and to a top portion 20a of an inner surface 20b of gussets 20.
When membrane 28 is sealed to bag 10, the seal captures the top
portion 20a of gussets 20 as well as front and back surfaces 12 and
14. Such a seal can be accomplished by methods commonly known in
the art, such as, for example, heat sealing.
[0059] When the article of manufacture is being manufactured, bag
10 is formed, the top portion thereof open. Ribs 36a of outer
surface 32 of membrane 28 can then be sealed to inner surface 12a
of front surface 12 and top portions 20a of gussets 20. The bag 10
is filled, and then ribs 36b of outer surface 32 can be sealed to
inner surface 14a of rear surface 14 and top portions 20a of
gussets 20 to seal bag 10 closed and form top surface 22.
[0060] Such a closure allows for top filling of bags. However, such
a closure could also be completely installed at the top of the bag,
and form the top surface 22, before filling and be used with a
bottom fill process without having the closure break or burst
during the bottom fill process.
[0061] Although membrane 28 provides excellent burst resistance, a
tear strength of greater than about 15 pounds per square inch
proves difficult for a user to open by hand. Because it is desired
that the article of manufacture of the present invention also be
easy for an ultimate consumer or user to open by hand, membrane 28
comprises a targeted opening region 38. Targeted opening region 38
has a tear strength, measured in the transverse or cross machine
direction by ASTM Method D-882, of from about 1 to about 15 pounds
per square inch, alternatively of from about 3 to about 12 pounds
per square inch, alternatively from about 4 to about 10 pounds per
square inch, alternatively from about 4 to about 9 pounds per
square inch, and alternatively from about 5 to about 7 pounds per
square inch.
[0062] During development of the bag of the present invention, it
was found that known non-reusable closures and tamper evident
features have opening regions that extend the entire length of the
membrane, i.e. essentially the entire width of the bag. Such
opening regions typically consist of one or more score lines,
perforations or other material-weakening features. However, it was
found that such opening regions, while being easily opened by a
consumer, by hand, also become a region of weakness and bursting
when bags filled with for example, 15 or more pounds of dry pet
food, are dropped, sometimes from as low as 18 inches. Such drops
are common in the shipping and handling of large, heavy bags
containing various particulate, flowable compositions and cause
damage and loss of product, and annoyance to retailers and
consumers.
[0063] Therefore, the burst-resistant bag 10 of the present
invention comprises targeted opening region 38 that comprises from
about 1% to about 90% of a length L of membrane 28. Alternatively
targeted opening region 38 comprises from about 1% to about 50% of
the length L of membrane 28, alternatively from about 1% to about
30% of the length L of membrane 28, and alternatively of from about
1% to about 10% of the length L of membrane 28. Furthermore, it was
found that when the opening region extends to, or is located
within, about 5% of either end 28a, 28b of the length L of membrane
28, even if the opening region only comprises a small percentage,
for example about 10-20%, of the length L of membrane 38, burst
resistance is decreased. Thus, even small opening regions, when
located at the end(s) 28a, 28b, of membrane 28, decrease burst
resistance. Therefore, the "targeted opening region" 38 of the
present invention means, and has the proviso that, the opening
region does not extend to within about 5% of either end 28a, 28b of
membrane 28. Targeted opening region 38 can be located anywhere
along the length L of membrane 28, within the definition of the
targeted opening region, or can be centered at a midpoint M along
the length L of membrane 28 and width W of bag 10. Targeted opening
region 38 is located at or near a midpoint m of the width w of
membrane 28, and is disposed inboard a distance from top edge 34 of
bag 10. FIGS. 7a-c illustrate various locations and sizes of
targeted opening region 38.
[0064] As can be seen in FIGS. 7a-c, targeted opening region 38 can
comprise a plurality of perforations 40 in membrane 28. Targeted
opening region 38 can also comprise and be formed by laser scoring,
heat scoring, or mechanical weakening of any type such as removing
a portion of material.
[0065] Also shown in FIGS. 7a-c, membrane 28 can also comprise
instructional indicia 42 on user-facing surface 30 of membrane 28.
Such instructional indicia 42 can comprise printing including
words, pictures, symbols, illustrations, and the like, to indicate
to the user where and how to open the non-reusable closure 26.
[0066] Membrane 32 can be formed from a material selected from the
group consisting of ethylene derived polymer, polypropylene,
polyester, polyolefins, homopolymer and/or co-polymer polyolefins,
and combinations thereof.
[0067] Particularly, membrane 32 can comprise an ethylene-derived
polymer selected from the group consisting of low density
polyethylene, high density polyethylene, ultra-low density
polyethylene, and combinations thereof. The particular combination
of material is selected based on balancing strength of the material
for burst resistance with openability for ease of use of the bag
10. The material is also devised and formed based on its ability to
seal securely to the plastic laminate of bag 10 to provide the
required seal strength of at least about 1,600 pounds per square
inch. The material of the membrane can be a co-extruded blend of
low density polyethylene, high density polyethylene, and ultra
low/very low density polyethylene, with ultra low/very low density
polyethylene forming ribs 36a and 36b such that the ribs seal to
the inner surfaces of the bag at a temperature of less than about
68.degree. C. The number of ribs 36a, 36b can depend on the width w
of the membrane. The spacing of the ribs 36a, 36b on membrane 28
can depend on the type and strength of seal desired.
[0068] In addition to finding a particular material for the
membrane 28 that provides burst resistance and allows for
openability, the dimensions of membrane 28 are important with
respect to burst resistance, seal strength, ease of sealing during
manufacturing, and openability. Membrane 28 has a width w of from
about 1.5 inches to about 3 inches. Alternatively, membrane 28 has
a width of from about 2 inches to about 3 inches. Alternatively,
membrane 28 has a width of about 3 inches. When the total width w
of the membrane 28 is about 3 inches, there can be about ten to
fifteen (10-15), alternatively about fourteen (14) ribs 36a, 36b
outer surface 32, as illustrated previously in FIG. 5.
[0069] Production and creation of the particular plastic laminate
of the present invention proved challenging. Although plastic
laminates are known, it proved difficult to construct an
appropriate laminate. Bags containing particulate, flowable
compositions are often dropped during shipping and handling.
Conventional, commercially available such bags often burst when
dropped from a height of as low as 18 inches, when filled with as
little as 15 pounds of composition. Such bursting causes damage and
lost product as well as messes and annoyance to retailers and
consumers. In particular, bags that have reclosable features tend
to burst at the site of the reclosable feature. Thus, currently
available resealable feed bags are generally not available in
capacities greater than about 15 pounds, and/or have the reclosable
feature taped over, or otherwise additionally reinforced.
[0070] When bags containing large amounts of particulate, flowable
compositions burst, several elements of the bag can fail. If the
bag has a reclosable feature, the forces generated by a drop of the
bag can cause the composition contained therein to burst through
the reclosable feature. The seals which form the bag can separate
and fail. The material from which the bag itself is made, for
example, the plastic laminate, can tear or burst open. The material
from which the laminate is made, as well as the thickness of the
laminate affect its burst resistance.
[0071] Therefore, it was necessary to create an appropriate
laminate having a balance of strength and stretchability (measured
by tensile strength), flexibility and stiffness (measured by secant
modulus), texture, thickness, and cost-effectiveness. Particular
laminates may have a high tensile strength, and therefore a high
resistance to stretching, which is useful to some degree. However,
such a laminate may be brittle or stiff (i.e. have a high secant
modulus), and because it resists stretching, may burst easily, and
therefore would not be useful in bags of the present invention.
However, other laminates that may be very stretchable (i.e. have a
low tensile strength), and therefore, resistant to bursting, would
also not be suitable, because such a laminate may result in bulges
or unsightly deformations after shipping, handling, and likely
dropping. In addition, a laminate usable with the present invention
must also have a suitable texture, and not be too slippery. Bags
containing at least about 15 pounds of a particulate, flowable
composition can be difficult to pick up and carry because of the
weight of material contained therein. Thus, bags containing such
materials should ideally not be slippery or hard to grip.
[0072] In addition, the laminate must be securely sealable to form
the bag, by methods known the art such as heat sealing. The
laminate must be cost-effective as well, and plastic laminate bags
are more costly than traditional paper feed bags. Thus, as thin a
layer of laminate as possible is desired. However, the thickness of
the laminate in combination with its composition affects its
likelihood to burst if dropped. Thus, material composition and
thickness must be considered.
[0073] Bag 10 of the present invention therefore has a seal
strength of at least about 1,600 pounds per square inch as measured
by ASTM Method D-882. Alternatively, bag 10 has a seal strength of
at least about 1,800 pounds per square inch.
[0074] The plastic laminate forming the bag has a tensile strength
of at least about 3,400 pounds per square inch as measured in both
the machine and transverse or cross machine directions by ASTM
Method D-882. Alternatively, the plastic laminate has a tensile
strength of at least about 3,500 pounds per square inch, and
alternatively of at least 3,800 pounds per square inch.
[0075] The plastic laminate of the bag has a secant modulus of from
about 50,000 to 110,000 pounds per square inch, as measured in both
the machine and transverse or cross machine directions by ASTM
Method D-882.
[0076] Bag 10 can be formed from a plastic laminate selected from
the group consisting of ethylene-derived polymer, polypropylene,
polyester, teraphthalates, polyolefins, homopolymer and or
co-polymer polyolefins, woven polypropylene, and combinations
thereof. More particularly, the plastic laminate can be selected
from the group consisting of ethylene-derived polymers such as
polyethylenes in combination with teraphthalates such as
polyethylene teraphthalate (PET). In order to be sealable to itself
and to the material of a non-reusable closure, if one is employed,
the material of the inner surface of the laminate has a relatively
low melting point such that it melts to enable heat sealing,
whereas the outer surface has a higher melting point such that it
does not melt during heat sealing. Thus, an outer layer can be
polyethylene teraphthalate (PET), and an inner layer can be a
co-extruded blend of linear low density polyethylene, medium
density polyethylene, and linear low density polyethylene. As used
herein the densities of polyethylene, "low", "medium", "high",
"ultra low/very low", have meanings as used and understood in the
art for such materials.
[0077] The plastic laminate has a thickness of from about 130 to
about 200 microns. Alternatively, the plastic laminate has a
thickness of from about 140 to about 170 microns.
[0078] In addition to aiding in enabling bag 10 to be
burst-resistant, the plastic laminate must provide oxygen and
moisture barrier properties. It has been shown that plastic is a
better oxygen and moisture barrier than traditional paper for pet
foods. It has also been shown that fats, carbohydrates, proteins,
and other components commonly found in pet foods oxidize over time
when exposed to air. Furthermore, it has been shown in palatability
tests that animals prefer, over time, food stored in plastic bags
versus that stored in paper bags. Thus, the articles of manufacture
of the present invention also provide enhanced palatability of the
oxidizable compositions contained therein.
[0079] Therefore, a preferred plastic laminate has an oxygen
transmission rate of less than about 6.5 cc/100 in.sup.2/24 hours,
as measured by ASTM Method D-3985, and alternatively of less than
about 6.2 cc/100 in.sup.2/24 hours. A preferred plastic laminate
also has a moisture vapor transmission rate of less than about 0.1
grams/100 in.sup.2/24 hours, when measured by ASTM Method F-1249,
and alternatively of less than about 0.8 grams/100 in.sup.2/24
hours.
[0080] In another embodiment of the present invention, as shown in
FIGS. 1 and 2, bag 10 can further include a reusable closure 44. As
described above, the dimensions and proportions of bag 10 are such
that they provide burst resistance and enhanced stability. Thus,
bag 10 is stable when placed on bottom surface 16. The plastic
laminate also provides oxygen and moisture barrier properties to
enable the composition to be stored in bag 10 over time. Therefore,
providing a reusable closure enables the end user consumer to
simply use bag 10 itself as the storage device for the
composition.
[0081] Non-limiting examples of reusable closures of the present
invention include a track and a slider system, a plastic zipper, a
metal zipper, a hook and loop fastening system, a threaded closure
device, a pressable sealing device, a snap sealing device,
resealable adhesive, magnetic sealing device, electrostatic sealing
device, and combinations thereof.
[0082] Reusable closure 44 is disposable at top edge 34 of bag 10,
as shown in FIGS. 1 and 2. Alternatively, reusable closure 44 is
disposable a distance inboard from top edge 34 of said bag.
[0083] In another embodiment of the present invention, bag 10 can
comprise both a non-reusable closure and a reusable closure.
[0084] As described above, bag 10 is not only burst-resistant but
stable as well, such that it can be used as a reusable storage
container. As described above the proportions and dimensions of bag
10 provide stability. Therefore, bag 10 has a tip angle of from
about 10.degree. to about 50.degree., and alternatively has a tip
angle of from about 20.degree. to about 30.degree.. Tip angle is
measured using ASTM Method 6179.
[0085] Bag 10 should also be provided with a means for equalizing
air pressure within the bag, to assist in providing burst
resistance and to provide an appealing visual appearance to the
bag. However, such means for equalizing air pressure must also
prevent infestation, i.e. prevent undesirable organisms form
entering the bag.
[0086] Air pressure equalization means can allow air to escape from
and enter bag 10. It is important to allow air to escape from bag
10 during shipping and handling of the bags. When bags are stacked
on pallets for shipping, the weight of the bags on top of each
other can cause the bags to burst if there is no way for air to
escape from the bags. However, once air is squeezed out of the
bags, the bags can have an unappealing, `vacuum packed`, lumpy
appearance. Thus, it is desirable to allow air back into the bags
once the bags are unloaded for display and sale.
[0087] Air pressure equalization can be accomplished by providing a
plurality of perforations 46 in at least one side of bag 10, for
example in each side gusset 20 as shown in FIGS. 1 and 2.
Perforations 46 can be less than about 90 micrometers in diameter,
and alternatively less than about 70 micrometers in diameter, in
order to allow air to pass therethrough but prevent
infestation.
[0088] In addition, one or more gaps (not shown) can be provided at
a seal of the bag, for additional passage of air. The gap(s) can be
formed by interrupting the heat sealing process, and such seals are
known in the art as "skip gap" seals. To form such a `skip gap
seal` a non-continuous seal bar can be used, i.e. a seal bar having
one or more gaps thereon wherein the gapped part of the seal bar
would not touch the material being sealed, thus leaving an unsealed
portion or "gap". Such a `skip gap seal` can be formed on the seal
formed at the bottom of the bag, at the seal formed when attaching
a first portion of the membrane to the front surface of the bag, or
when attaching the second portion of the membrane to the rear
surface of the bag. A `skip gap seal` can be formed, for example in
the final seal sealing the bag closed once it has been filled. Each
gap can be of from about 70 .mu.m to about 10 mm in length. If no
non-reusable closure is used, gap(s) can be formed in any of the
seals used to form the bag, as required for appropriate, desired
air equalization.
[0089] The gap(s) can be straight sided, and have a cylindrical or
tubular shape, or can be shaped and/or curved and of a length that
would still allow air to pass therethrough, but which would provide
a barrier to infestation (i.e. provide a longer, more complicated
path for potentially infesting organisms). Any shaped gap can be
incorporated or formed into the seal bar of the heat sealing
apparatus, as would be understood by those skilled in the art.
Method of Enhancing Palatability
[0090] The present invention also includes methods of enhancing
palatability of an oxidizable particulate, flowable composition
after storage comprising the steps of: [0091] a. providing a
plastic laminate bag comprising: [0092] i.) two side surfaces each
having a gusset therein and connecting the front and rear surfaces;
[0093] ii.) a closure system comprising a reusable closure and a
non-reusable closure, wherein said non-reusable closure comprises a
membrane having a targeted opening region, the targeted opening
region having a tear strength of from about 4 to about 10 pounds
per square inch; [0094] wherein the plastic laminate has a
predetermined oxygen transmission rate and a predetermined water
vapor transmission rate; [0095] b. filling the plastic laminate bag
with at least about 15 pounds of an oxidizable, particulate,
flowable composition; [0096] c. sealing the plastic laminate bag
closed; thereby preventing oxidation and spoilage and enhancing the
palatability of the composition contained therein.
[0097] The plastic laminate usable with the method has an oxygen
transmission rate of less than about 6.5 cc/100 in.sup.2/24 hours,
alternatively less than about 6.2 cc/100 in.sup.2/24 hours. The
oxygen transmission rate is measured, as described above, by ASTM
Method D-3985. The plastic laminate has a moisture vapor
transmission rate of less than about 0.1 grams/100 in.sup.2/24
hours, alternatively less than about 0.8 grams/100 in.sup.2/24
hours. The moisture vapor transmission rate is measured, as
described above, by ASTM Method F-1249.
EXAMPLES
[0098] ASTM Method 5276-98 (Reapproved 2004) "Standard Test Method
for Drop Test for Loaded Containers by Free Fall" contains
provisions for dropping variously shaped containers to assess
various parameters such as finding an average drop height to
failure, or for attaining pass/fail data. Bags of the present
invention are subjected to these tests from heights of up to 6
feet, as a specification for shipping and handling
requirements.
[0099] See in particular sections A1.1, A1.3. When testing bags of
the present invention, the test is a pass/fail test because
required drop heights are specified. Based on experience packaging,
shipping, and handling such bags, a specification is set that such
bags containing at least about 20 pounds of particulate, flowable
material, must pass a free fall drop from at least about 6 feet.
When the bags contain at least about 40 pounds of particulate,
flowable material, they must pass a free fall drop from at least
about 4 feet. Failure occurs if any of the seals of the bag, any
closures (whether reusable or non-reusable), or the bag material
tears, splits, separates, punctures, deforms, bulges, and/or
leaks.
[0100] The apparatus used for such a drop conforms to section 5 of
ASTM Method 5276-98. Specifically the apparatus used is a L.A.B.
Model 160A Drop Tester. The bags can be dropped on each of the six
surfaces of the bag, and in particular must pass the drop test from
the given drop height on at least one of the side surfaces. Single
drops are performed, as in section A2.2.1, and drops on all six
surfaces are performed, as in section A2.2.8. In particular, drops
are performed on one or both of the two side surfaces, as in
section A2.2.10, because the two side surfaces are those determined
most likely to fail. The impact surface is concrete, as specified
in section 5.1.5.1, and complies with sections 5.1.5.3-5. When the
bags are dropped on each surface, they are dropped such that the
drop complies with sections 8.4.1-8.5.
Example 1
[0101] A bag of the present invention can be constructed as
follows.
[0102] A plastic laminate film, comprising a 12 micron thick layer
of polyethylene teraphthalate ("PET") bonded by adhesive lamination
to a 140 micron thick co-extruded layer of metallocene linear low
density polyethylene, medium density polyethylene, and metallocene
linear low density polyethylene, (available for example from
Exopack, Spartanburg, S.C., USA) is used for forming the bag. Once
the bag is formed, the co-extruded polyethylene layer forms the
inner surface and the PET layer forms the outer surface of the
bag.
[0103] The sides of the bag are gusseted. The two edges of each
side gusset on each side of the bag are sealed to form two edge
seals on each side, resulting in four edge (4) seals, thus forming
a "quad seal" bag The bag is sealed at the bottom by conventional
heat sealing, capturing the bottom of the side gussets therein and
forming a bottom surface. The side gussets are also sealed at the
bottom of f the bag with a "K-seal" as is known in the art, to
allow the bottom surface to be flattenable.
[0104] A non-reusable closure membrane formed from a blend of low
density polyethylene and ultra low density polyethylene is
attached, by co-extrusion therewith, to a track of a slider and
track zipper, for example a Slide-Rite.RTM. zipper from Pactive
Corp., Lake Forest, Ill., USA. A track of a slider track zipper
device is formed high density polyethylene. The track and the
membrane are co-extruded. The membrane has a width w of about 3
inches as measured from inner edge to inner edge of the track. The
membrane has a targeted opening region of 1.5 inches in length,
disposed along the length of the membrane, and formed form a
plurality of perforations. The targeted opening region is formed
centered at a midpoint m of the width w of the membrane, and
centered at a midpoint M of the length L of the membrane. See FIG.
7C. The targeted opening region has a tear strength (as measured by
ASTM Method D-882) of between about 5-7 pounds per square inch.
[0105] The non-reusable closure membrane attached to the reusable
track and slider closure is attached by heat sealing one side of
the outer surface of the membrane to an inner surface of the front
surface of the bag. The inner and outer surfaces of one half of
each side gusset are captured by the seal. The bag is filled with
20 pounds of dry pet food. With the dimensions described herein,
20% headspace is provided and results in 5.5 inches of bag height
remaining above the height of the product, which enables proper
sealing of the bag. The second side of the outer surface of the
membrane of the non-reusable closure is then heat sealed to the
inner surface of the rear surface of the bag to close the bag. The
inner and outer surfaces of the other half of each side gusset are
captured by the final seal.
[0106] The bag has a height of 25 inches, a width of 13.25 inches,
and a depth of 6.5 inches. Height dimensions have a tolerance of
about 0.12 inches. Width dimensions have a tolerance of about 0.25
inches. Depth dimensions have a tolerance of 0.6 inches. The ratio
of width to height is 0.6. The ratio of depth to height is
0.25.
[0107] A bag as described in this example will pass a drop test
conducted according to ASTM Method D-5276-98 (Reapproved 2004)
Standard Test Method for Drop Test of Loaded Containers by Free
Fall, when dropped on any and all six surface, particularly the two
side surfaces, from a height of 6 feet when filled with 20 pounds
of dry dog food.
Example 2
[0108] An alternative embodiment of a bag of an article of
manufacture of the present invention can be made as follows.
[0109] A plastic laminate film, comprising a 12 micron thick layer
of polyethylene teraphthalate ("PET") bonded by adhesive lamination
to a 165 micron thick co-extruded layer of metallocene linear low
density polyethylene, medium density polyethylene, and metallocene
linear low density polyethylene, (available for example from
Exopack, Spartanburg, S.C., USA). is used for forming the bag. Once
the bag is formed, the co-extruded polyethylene layer forms the
inner surface and the PET layer forms the outer surface of the
bag.
[0110] The sides of the bag are gusseted. The two edges of each
side gusset on each side of the bag are sealed to form two edge
seals on each side, resulting in four edge (4) seals, thus forming
a "quad seal" bag The bag is sealed at the bottom by conventional
heat sealing, capturing the bottom of the side gussets therein and
forming a bottom surface. The side gussets are also sealed at the
bottom of f the bag with a "K-seal" as is known in the art, to
allow the bottom surface to be flattenable.
[0111] A non-reusable closure membrane formed from a blend of low
density polyethylene and ultra low density polyethylene is
attached, by co-extrusion therewith, to a track of a slider and
track zipper, for example a Slide-Rite.RTM. zipper from Pactive
Corp., Lake Forest, Ill., USA. A track of a slider track zipper
device is formed high density polyethylene. The track and the
membrane are co-extruded. The membrane has a width w of about 3
inches as measured from inner edge to inner edge of the track. The
membrane has a targeted opening region of 1.5 inches in length,
disposed along the length of the membrane, and formed form a
plurality of perforations. The targeted opening region is formed
centered at a midpoint m of the width w of the membrane, and
centered at a midpoint M of the length L of the membrane. See FIG.
7C. The targeted opening region has a tear strength (as measured by
ASTM Method D-882) of between about 5-7 pounds per square inch.
[0112] The non-reusable closure membrane attached to the reusable
track and slider closure is attached by heat sealing one side of
the outer surface of the membrane to an inner surface of the front
surface of the bag. The inner and outer surfaces of one half of
each side gusset are captured by the seal. The bag is filled with
40 pounds of dry pet food. With the dimensions described herein,
20% headspace is provided and results in 5.5 inches of bag height
remaining above the height of the product, which enables proper
sealing of the bag. The second side of the outer surface of the
membrane of the non-reusable closure is then heat sealed to the
inner surface of the rear surface of the bag to close the bag. The
inner and outer surfaces of the other half of each side gusset are
captured by the final seal.
[0113] The bag has a height of 29 inches, a width of 17.5 inches,
and a depth of 7.25 inches. Height dimensions have a tolerance of
about 0.12 inches. Width dimensions have a tolerance of about 0.25
inches. Depth dimensions have a tolerance of 0.6 inches. The ratio
of width to height is 0.6. The ratio of depth to height is
0.25.
[0114] A bag as described in this example will pass a drop test
conducted according to ASTM Method D-5276-98 (Reapproved 2004)
Standard Test Method for Drop Test of Loaded Containers by Free
Fall, when dropped on any and all six surfaces, particularly the
two side surfaces, from a height of 4 feet when filled with 40
pounds of dry dog food.
[0115] The dimensions and values disclosed herein are not to be
understood as being strictly limited to the exact numerical values
recited. Instead, unless otherwise specified, each such dimension
is intended to mean both the recited value and a functionally
equivalent range surrounding that value. For example, a dimension
disclosed as "40 mm" is intended to mean "about 40 mm."
[0116] All documents cited in the Detailed Description of the
Invention are, in relevant part, incorporated herein by reference;
the citation of any document is not to be construed as an admission
that it is prior art with respect to the present invention. To the
extent that any meaning or definition of a term in this document
conflicts with any meaning or definition of the same term in a
document incorporated by reference, the meaning or definition
assigned to that term in this document shall govern.
[0117] While particular embodiments of the present invention have
been illustrated and described, it would be obvious to those
skilled in the art that various other changes and modifications can
be made without departing from the spirit and scope of the
invention. It is therefore intended to cover in the appended claims
all such changes and modifications that are within the scope of
this invention.
* * * * *